So this chum of mine says he needs a new compressor ( paint guitars ) because his old one is siezed.
He bought one.
Upon closer inspection the centrifugal stitch is B/O and just needs to be cleaned up.
Got me to thinking how many times others may have been mystified by the motor that hums but won't roll.
Simple adivce I have is to mark the location of parts and careful know the rear end bell off the motor and inspect your switch ( has a set of point s that wear out just like a small egine ).
Many of your house hold single phase motors use this same switch arangement. The need this switch for a lack of a more complicated explaination to pull the rotor around on start up ( they can't decided what way top turn with a little help ). Once at about 75% speed this switch opens and allows the regular interactions of magnetic fields inside to pull the motor a long in the right direction.
Brush type AC motors ( Universal type )
Now and then you might discover motors with brushes.
Good rule of thumb is to replacement once your down to 1/3.
Never use sand paper to clean the commutator this causes rapid wear because the abrassive burries itself in the soft copper bars.
Stoning and under cutting of coms is not something most people do these days. Odds are you can get more life just keeping the motors clean and change the brushes a few times then if you try and get fancy and tune them up with a stone or scratch them all to hell with a knife.
Repulsion Start Induction.
Very old school and I am dating myself bringing these up but there are a lot of good old tools ( particularly compressors and pumps ) that used these ( I figuere they stopped making them inthe 50s to be honest ).
These need to be kept clean and the comes resurfaced on lathe. the centrifugals need to short and lift smoothly and to change direction you need to shift the brush rigging about 15 Deg one way or the other.
Confused?
So are 95% of electricians out there these days confronted with one of these ( best see a winder for service and the older the guy the better )
OIL:
Never use auto oil on bronze bushing.
3 in 1 makes a blend for small electric motors and larger ones tend to get away with ND 30. Detergents in modern oil loosen up all kind of crud in the motor and this turns abrasive earing them up of gumming them. No more than a few drop a year for a tool you rarely use more than once a week.
Hope this helps.....
He bought one.
Upon closer inspection the centrifugal stitch is B/O and just needs to be cleaned up.
Got me to thinking how many times others may have been mystified by the motor that hums but won't roll.
Simple adivce I have is to mark the location of parts and careful know the rear end bell off the motor and inspect your switch ( has a set of point s that wear out just like a small egine ).
Many of your house hold single phase motors use this same switch arangement. The need this switch for a lack of a more complicated explaination to pull the rotor around on start up ( they can't decided what way top turn with a little help ). Once at about 75% speed this switch opens and allows the regular interactions of magnetic fields inside to pull the motor a long in the right direction.
Brush type AC motors ( Universal type )
Now and then you might discover motors with brushes.
Good rule of thumb is to replacement once your down to 1/3.
Never use sand paper to clean the commutator this causes rapid wear because the abrassive burries itself in the soft copper bars.
Stoning and under cutting of coms is not something most people do these days. Odds are you can get more life just keeping the motors clean and change the brushes a few times then if you try and get fancy and tune them up with a stone or scratch them all to hell with a knife.
Repulsion Start Induction.
Very old school and I am dating myself bringing these up but there are a lot of good old tools ( particularly compressors and pumps ) that used these ( I figuere they stopped making them inthe 50s to be honest ).
These need to be kept clean and the comes resurfaced on lathe. the centrifugals need to short and lift smoothly and to change direction you need to shift the brush rigging about 15 Deg one way or the other.
Confused?
So are 95% of electricians out there these days confronted with one of these ( best see a winder for service and the older the guy the better )
OIL:
Never use auto oil on bronze bushing.
3 in 1 makes a blend for small electric motors and larger ones tend to get away with ND 30. Detergents in modern oil loosen up all kind of crud in the motor and this turns abrasive earing them up of gumming them. No more than a few drop a year for a tool you rarely use more than once a week.
Hope this helps.....